<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>
    <p>jquery test 1</p>
    <p>jquery test 2</p>
    <p>jquery test 3</p>

    <div id="div1">
        <p>jquery test in div</p>
    </div>

    <script type="text/javascript" src="./my-jquery.js"></script>
    <script type="text/javascript">
        var $p = $('p')
        $p.css('font-size', '40px')
        alert($p.html())

        var $div1 = $('#div1')
        $div1.css('color', 'blue')
        alert($div1.html())
    </script>
</body>
</html>